US large-scale farming is conducted with the assumption that plants only need potassium, nitrogen, and phosphorous. These elements are delivered to the soil as fertilizers manufactured in a variety of ways and injected into the soil. The plants are grown as monoculture (large fields with only one species grown). To prevent competing plants, manufactured herbicides are applied. To prevent predation by bugs, manufactured insecticides are applied. The result is large productivity of seemingly healthy produce for both human and livestock consumption after harvesting. This assumes that these traditional plants that have provided humanity with sustenance for thousands of years is due solely to their genetic makeup: if they look healthy they are healthful.
The soil is a non-living substrate that only mechanically holds the plant in place and absorbs the manufactured herbicides and pesticides. After harvest, the soil is barren until the next crop cycle. This approach is only a few decades old, inspired by chemical manufacturers that wanted to find a use for their factories after World War II ended their lucrative poison, artillery, and fuel contracts.
An alternative perspective suggests that there exists many nutrients that play a role with small but crucial quantities that are poorly understood. If soil is alive and filled with worms, bugs, bacteria, and fungus there will be as many of these “micro nutrients” as possible. There will also be a vast array of naturally forming chemicals that play no direct role. An ecology of living, competing organisms will provide a wide variety that is more likely to include the micro nutrients; the more variety, the more likely. Plants grown in this soil have the opportunity to absorb these nutrients as they are required under all the different scenarios where they are needed. The resulting crop is produced by a more completely expressed genome because the plant makes the selection of what nutrients it requires when it needs them. Need used here may be better expressed as a want. The plant will live without them, but it won’t fully represent that plant’s full nutritional capacity.
When you feed livestock or humans with fully expressed produce, they have access to all the crop has to offer. This is the plant that humans have consumed historically. There are micro nutrients that both come from the soil and are manufactured in the plant due to the availability of micro nutrients in the soil. The model is one of free selection, the more the better.
The same selection model can be seen with livestock. We start with a pasture that has a wide variety of plant and animal life including bacteria and fungus in the soil. The livestock has choices driven by desire that evolution has tuned. The animal will receive the variety of micro nutrients and be healthier and provide a wider range of micro nutrients both from what it eats and what it is now capable of manufacturing since it is well supplied. The resulting meat, eggs, milk, cheese, etc has more nutrition for the human consumer. Large scale livestock production feeds animals with no choice and assumes they are receiving enough of what they need. And the feeds are derived from crops that are produced without variety.
Our human desire for particular foods has been evolution-tuned based on the nutrition found in plants and animals historically but is not as available in the large-scale “factory” produce. So our bodies will encourage us to consume something but that something doesn’t satisfy the need. We end up eating more in an effort to acquire what is missing and only gain weight, become less healthy and require even more missing micro nutrition.